Place the salmon, onion, spices, coriander and rice in a large bowl and mix well. Stir in the egg and season well. Mix in enough of the flour to form a stiff mixture. Using wet hands, shape into 20 small balls.
Heat the oil in a large frying pan, add the bhajis and fry for 3–4 minutes, turning once, until golden.
Meanwhile, mix together the yogurt, cucumber and mint in a bowl. Serve with the bhajis.